JPH07223111A - Cutting device for thin metal pipe - Google Patents

Abstract

PURPOSE:To continuously cut a metal pipe by simple control and to finish the cut surface of the metal pipe beautifully. CONSTITUTION:An attaching part 32 is provided with a roller 40 for supporting a part of the outer peripheral surface of a metal pipe 3 to be cut and a cutter 42 for cutting this metal pipe 3. A core 58 abutting on or lowering close to the inner peripheral surface of the metal pipe 3 is provided in a position shifted from the hitting position of the cutter 42 to a pipe making machine 1 side on the inner side of the metal pipe 3. This core 58 is provided with a guiding element 59 and permanent magnets 62 and 62 installed in positions non-aligned with the cutter 42. A magnetic material 69 formed annularly for allowing the metal pipe 3 to be freely inserted is supported in a position aligned with these permanent magnets 62 and 62 on the outer peripheral surface of the metal pipe 3. During cutting work, by means of the magnetic attractive forces of the permanent magnets 62 and the magnetic material 69, the core 58 incorporating the permanent magnets 62 therein moves together with the metal pipe 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION A cutting device for thin-walled metal pipes according to the present invention is incorporated into, for example, a thin-walled electric resistance welded pipe (hereinafter simply referred to as thin-walled metal pipe) production line and continuously manufactured.
It is used to cut a long thin metal tube that is sent out to a predetermined size.

[0002]

2. Description of the Related Art For example, in the case of manufacturing a stainless steel electric resistance welded pipe for manufacturing a bellows for an exhaust pipe joint, a strip-shaped metal thin plate sent from an uncoiler by a pipe forming machine is rolled into a tubular shape. Then, both ends of the strip-shaped thin metal plate are abutted against each other, and the ends are electrically welded to each other to form a long metal pipe. Such a long metal tube is cut into a predetermined size in the next step. By the way, since the metal pipe manufacturing work is continuously performed without stopping the metal pipe sent from the pipe making machine, the work of cutting to the predetermined size is
The cutting device is moved at the same speed as the feeding speed of the metal pipe.

As a method for cutting the metal tube, a method called metal saw cutting in which a rotary saw tooth (metal saw) is directly pressed against the metal tube to cut the inside of the metal tube while leaving a hollow, or a sharp blade is used to directly cut the metal tube. A method called shear cut, which presses against the metal tube to cut the inside of the metal tube while leaving it hollow, has been conventionally known.

However, each of the above-mentioned cutting methods is effective when the metal tube is thick, but when the metal tube is thin, burrs are generated on the cut surface or the cutting edge portion is It cannot be used as it is due to deformation, etc., and post-processing such as trimming the cutting edge is required.

In order to eliminate such inconvenience, a core having an outer diameter dimension slightly smaller than the inner diameter is inserted into the inside of a long thin metal tube before cutting, and the long thin metal tube is cut. A core insertion type cutting device is conceivable, in which the rotary blade is pressed against a portion of the outer peripheral surface of the core close to the edge of the core, and the rotary blade is revolved while revolving to rotate the core. Partly implemented.

FIG. 9 schematically shows an example of the core insertion type cutting device described above. Incidentally, FIG. 9 shows the outline of the cutting device, and a part of the cutting device is omitted. The pipe-making machine 1 rolls a strip-shaped thin metal plate 2 to bring the edges into contact with each other, and welds the butted portions to form a thin-walled metal pipe 3 and sends the thin metal pipe 3 backward. The cutting device is provided behind the pipe making machine 1. That is, on the floor surface located below the thin-walled metal pipe 3 delivered from the pipe-making machine 1, the first linear guide 4 extending in the direction parallel to the feed direction of the thin-walled metal pipe 3 (left-right direction in FIG. 9). Are installed. Further, a reciprocally movable first table 5 is provided on the first linear guide 4. The first table 5 is driven via a rack and pinion 7 by a first motor 6 which can rotate normally and reversely, and moves to a position shown in the drawing along with a cutting operation.
After the thin metal tube 3 is cut, the first motor 6 is rotated in the opposite direction to
Return to the cutting start position near the pipe making machine 1 (to the right in FIG. 9).

A cutting machine 8 is provided above the first table 5.
Is provided. This cutting machine 8 includes a cutter 10 that can be raised and lowered via a cylinder 9, a support roller 11 that rotates while supporting the thin-walled metal tube 3, and the cutter 10 and the support roller 11 with the thin-walled metal tube 3 as the center of rotation. A gear unit 12 for rotating (revolving) and a third motor 13 for rotationally driving the gear unit 12 are provided. Therefore, when cutting the thin metal tube 3, the cutter 10 cuts the thin metal tube 3 while revolving around the thin metal tube 3 while rotating on its own axis.

On the floor surface behind the cutting machine 8 (on the left side in FIG. 9), there is a direction parallel to the feeding direction of the thin metal tube 3,
A second linear guide 14 is provided. The second table 15 is provided on the second linear guide 14 so as to be reciprocally movable. This second table 15
It is driven through a rack and pinion 17 by a second motor 16 which is capable of normal rotation and reverse rotation, and is reciprocally movable along the second linear guide 14.

A core exchanger 18 is provided on the upper surface of the second table 15. The core exchanger 18 includes a rotary shaft 19 and an upper and lower rotary shaft 19 fixed to the tip of the rotary shaft 19.
A pair of supporting arms 20, 20 and this pair of supporting arms 20, 20
Of the pair of stoppers 21 and 21 provided at the tips of the cores and the cores 22 and 22 extending from the pair of stoppers 21 and 21.
It has and. The cores 22 and 22 are thin metal tubes 3
It has a length approximately equal to the length of the tip to be cut. When the cutting machine 8 is operated, its installation position is regulated so as to prevent interference between the tip of the core 22 inserted into the tip of the thin metal tube 3 and the cutting edge of the cutter 10.

In the portion between the pair of cores 22 and 22,
Clampers 24, 24 are provided. This clamper 24,
After cutting the long thin metal tube 3, the reference numeral 24 holds the cut thin metal tube 23 positioned below as the rotary shaft 19 rotates and inserts it into the cut thin metal tube 23. The thin metal tube 23 is prevented from moving together with the core 22 when the core 22 is moved backward. After the core 22 is completely removed from the cut thin metal tube 23, the clampers 24 and 24 are opened, and the cut thin metal tube 23 is dropped and discharged.

Since the core insertion type cutting device known in the prior art is constructed as described above, the long thin metal pipe 3 fed from the pipe forming machine 1 is supported by the supporting roller 11. While being sent out, it passes through the cutting machine 8. When the tip of the thin-walled metal pipe 3 reaches a predetermined position, the first motor 6 is activated to move the first table 5 stopped at the cutting start position at the same speed as the thin-walled metal pipe 3. Move in the same direction with.

At the same time, the upper core 22 is inserted into the thin metal tube 3. That is, by driving the second motor 16, the second table 15 is moved to the right in FIG. 9 at the first speed. Then, the second table 15 is stopped in a state where the distance between the stopper 21 and the tip surface of the thin metal tube 3 becomes a predetermined dimension (for example, 10 mm to 20 mm).

Next, the second motor 16 is immediately rotated in the reverse direction to move the second table 15 to the left in FIG. 9 at a second speed slightly slower than the feeding speed of the thin metal tube 3. . After the tip of the thin-walled metal pipe 3 (the left end in FIG. 9) contacts the stopper 21, the second table 15 is moved to the left in FIG. 9 at the same third speed as the thin-walled metal pipe 3. Move toward. At this time, the first table 5 is
The rotation of the first motor 6 causes the thin metal tube 3 to move at the same speed and in the same direction.

In this state, the cutter 10 rotates and descends toward the peripheral surface of the thin metal tube 3 to revolve around the thin metal tube 3 and cut the thin metal tube 3. When the cutting is completed, the cutter 10 is returned to the original position as shown by the drawing of the cylinder 9. After the thin metal tube 3 is cut, the first table 5 starts moving rightward in FIG. At the same time, the core exchanger 18 rotates 180 degrees to move the cut thin-walled metal pipe 23 downward with the core 22 still inserted, and then the cut thin-walled metal pipe 2
3 is gripped by a pair of clampers 24, 24. In this state, the second table 15 moves leftward in FIG. 9 at a fourth speed higher than the moving speed of the thin metal pipe 3 and stops at a predetermined position.

When the second table 15 is stopped, the clampers 24, 24 are opened and the cut thin metal tube 23 is dropped on a conveyor (not shown). And
The above operation is repeated to perform the next cutting operation. By continuously performing such a cutting operation, the thin metal pipe 3 delivered from the pipe forming machine 1 is continuously cut into a predetermined length dimension without stopping.

[0016]

However, in the conventional core insertion type cutting device described above, the moving speed of the second table 15 for moving the core 22 into and out of the thin metal tube 3 is set to It is necessary to change in four stages of speeds 1 to 4. Further, fine control such as synchronizing the first and second tables 5 and 15 is required. Therefore, these controls are NC controls. Therefore, this cutting device becomes large in size and extremely expensive. Furthermore,
It is difficult to smoothly insert the core 22 into the thin-walled metal pipe 3, and in extreme cases, the end faces of the thin-walled metal pipe 3 and the core 22 abut each other, so that the core 22 becomes thinner. It may not be possible to insert it inside.

The cutting device for thin-walled metal pipes according to the present invention solves all of the above-mentioned inconveniences, prevents the thin-walled metal pipes from being burred or deformed, and cleans the cutting face to improve the commercial value. This makes it possible to manufacture high-thin-wall metal tubes.

[0018]

A cutting device for thin-walled metal pipes according to the present invention, in any one of claims 1 and 4, is continuously fed from a pipe forming machine. It is provided below a thin, long thin metal tube, and can reciprocate in the same direction as the feeding direction of this thin metal tube and in the opposite direction,
A table that moves at the same speed as the feeding speed of the thin-walled metal pipe when moving in the same direction and a cutting machine that is provided on the upper surface of the table and cuts the thin-walled metal pipe are provided.

In particular, the thin-wall metal pipe cutting apparatus according to claim 1 is intended for a thin-wall metal pipe made of a nonmagnetic material, and the cutting machine satisfies the following requirements (1) to (3). I am trying. That is, it is provided with a mounting portion that rotates around the thin metal tube around the thin metal tube. A receiving member that is supported by a first pivot parallel to the thin-walled metal pipe and that revolves around the thin-walled metal pipe while partially supporting the outer peripheral surface of the thin-walled metal pipe is supported in the mounting portion. It is provided. A cutter is provided in a part of the mounting portion at a position substantially diametrically opposite to the receiving member with respect to the thin-walled metal pipe so as to be capable of advancing and retracting with respect to the outer peripheral surface of the thin-walled metal pipe. This cutter has a circular cutting edge as a sharp cutting edge,
The outer peripheral edge of the thin metal tube can be abutted against the outer peripheral surface of the thin metal tube while being supported by the second pivot parallel to the thin metal tube. Inside the thin metal pipe, a core is provided at a position displaced from the abutting position of the cutter to the pipe making machine side, and inside the thin metal pipe, at least the diametrical direction of the abutting position. The inner part is a hollow part. The core includes a guide element that comes into contact with or comes close to the inner peripheral surface of the thin metal tube, and a first magnetic element that is provided at a position deviated from the abutting position of the cutter. At the position on the upper surface of the table that faces the outer peripheral surface of the first magnetic element via the thin metal tube, a second magnetic element formed in an annular shape through which the thin metal tube can be inserted is supported. There is. At least one of the first magnetic element and the second magnetic element is a magnet, at least during the cutting operation between these first and second magnetic elements, a magnetic attraction force acts,
The core incorporating the first magnetic element moves together with the thin metal tube.

Further, in the apparatus according to the fourth aspect, the object is all thin-walled metal tubes regardless of whether they are made of non-magnetic material or magnetic material, and the cutting machine is It is characterized by meeting the requirements. That is, it is provided with a mounting portion that rotates around the thin metal tube around the thin metal tube. A receiving member that is supported by a first pivot parallel to the thin-walled metal pipe and that revolves around the thin-walled metal pipe while partially supporting the outer peripheral surface of the thin-walled metal pipe is supported in the mounting portion. It is provided. A cutter is provided in a part of the mounting portion at a position substantially diametrically opposite to the receiving member with respect to the thin-walled metal pipe so as to be capable of advancing and retracting with respect to the outer peripheral surface of the thin-walled metal pipe. This cutter has a circular cutting edge as a sharp cutting edge,
The outer peripheral edge of the thin metal tube can be abutted against the outer peripheral surface of the thin metal tube while being supported by the second pivot parallel to the thin metal tube. Inside the thin metal pipe, a core is provided at a position displaced from the abutting position of the cutter to the pipe making machine side, and inside the thin metal pipe, at least the diametrical direction of the abutting position. The inner part is a hollow part. The core includes a guide element that is in contact with or close to the inner peripheral surface of the thin metal tube. During the cutting operation, the core is moved together with the metal tube as the clamper that moves together with the table holds down the outer peripheral surface of the core via the metal tube. One end of the wire is connected to the rear end of the core,
The other end side of the wire is allowed to move the core during the cutting work, and is connected to a drawing means for drawing the wire after the cutting work is completed.

[0021]

Since the thin-wall metal pipe cutting device of the present invention is constructed as described above, a thin-wall metal pipe made of a non-magnetic material (in the case of the cutting device according to claim 1) or a magnetic non-magnetic pipe can be used. Regardless of magnetism,
All thin metal tubes (in the case of the cutting device according to claim 4) can be cut continuously with a relatively simple control and with clean cut surfaces.

That is, when the thin metal tube is cut, the core moves together with the thin metal tube at the same speed as the thin metal tube. After the cutting, the core is returned to the original predetermined position together with the table by the magnetic attraction force of the second magnetic element (in the case of claim 1) or by the drawing of the wire (in the case of claim 4). After that, the second magnetic element is moved in the feeding direction of the thin-walled metal tube (in the case of claim 1) or the core is pressed down through the thin-walled metal tube (in the case of claim 4). ), The core and the thin-walled metal pipe move in the same direction at the same speed, and the thin-walled metal pipe is cut during this movement. Therefore,
You can perform continuous cutting work with simple control without attaching or detaching the core.

[0023]

1 to 4 show a first embodiment of the present invention corresponding to claim 1. The cutting device according to the present invention, like the above-described conventional device, is a pipe-making machine for rolling a thin metal plate 2 and joining the edges thereof by welding or the like to form a long thin metal pipe 3 (electric resistance welded pipe). It is provided behind 1 (on the left side of FIG. 1). This cutting device is provided on a table 25 that is reciprocally movable in the same direction as the feeding direction of the thin metal tube 3 (left direction in FIG. 1) and in the opposite direction, and is provided on the upper surface of the table 25.
A cutting machine 26 for cutting the thin metal tube 3 is provided.

The table 25 is on the upper surface of the base 27,
It is supported on a linear guide 28 provided at a position below the thin metal pipe 3 continuously fed from the pipe making machine 1. Further, a speed tuning servomotor 29 is fixed to the rear end side (left side in FIG. 1) of the base 27 in the feeding direction. A screw rod 30 is connected to the output shaft of the servomotor 29, and a nut member 31 fixed to the rear end of the table 25 in the feed direction is screwed onto the screw rod 30. Therefore, the table 25 is moved to the linear guide 2 by rotating the speed tuning servomotor 29 in the normal or reverse direction.
8 Move back and forth. Also, the speed tuning servo motor 2
By controlling the rotation speed of the table 9, the moving speed of the table 25 can be freely changed. Then, the table 25 is moved in the feeding direction of the thin metal pipe 3 (leftward in FIG. 1).
When moving in the same direction as, the moving speed is the same as the feeding speed of the thin metal tube 3, and when moving in the opposite direction, the moving speed is as fast as possible.

The cutting machine 26 is provided with a mounting portion 32 and first and second clampers 33 and 34. Of these, the mounting portion 32 rotates around the thin-walled metal tube 3 around the thin-walled metal tube 3, and is configured as follows.

That is, as shown in FIGS. 1 to 4, the support ring 36 is supported inside the tapered cup 35 whose inner diameter gradually decreases from the opening end toward the bottom surface. This support ring 36
Are rotatably supported (incapable of axial displacement) on the table 25 by bearings (not shown). The first to third arms 37, 38, 39 are attached to one end portion (the left end portion in FIG. 4) of the support ring 36, and the respective tip portions of the support ring 36 are attached to the support ring 36.
It is provided in a state of protruding toward the axis center of. The first and second arms 37, 38 have tips of rollers 40, 4 to be described below at their distal end portions.
1, and a cutter 42, which will also be described below, is provided at the tip of the third arm 39. These first to third arms 37, 38, 39 are respectively inserted through the three through holes 43 provided at one end of the support ring 36. By providing a compression spring 44 between the base end portion protruding from the support ring 36 and the outer peripheral surface of the support ring 36, the first to third arms 37, 38, 39 are radially outwardly extended. It gives elasticity to face. The inner surface of the taper cup 35 and the end surfaces of the base ends of the arms 37, 38, 39 that come into contact with the inner surface are
Cover with a slippery material such as nylon, Delrin, PTFE, or oil-impregnated metal. The first and second arms 37, 38
May be fixed, and only the third arm 39 provided with the cutter 42 may be movable back and forth.

A first pivot 45 parallel to the thin metal tube 3 is provided at the tip of the first and second arms 37 and 38, and
Second pivots 46, which are also parallel to the thin metal tube 3, are provided at the distal ends of the third arms 39, respectively. Rollers 40 and 41, which are receiving members, are supported on the first pivot 45, and a cutter 42 is supported on the second pivot 46. The cutter 42 has a circular outer peripheral edge as a sharp cutting blade.

As described above, the first to third arms 37, 3
8 and 39 are urged by a compression spring 44, but with the relative movement of the support ring 36 toward the inner surface (the right surface in FIGS. 1 and 4) of the taper cup 35, the first to third The arms 37, 38, 39 of the are directed toward the outer surface of the thin metal tube 3 and are extruded inward in the diameter direction. Therefore, the rollers 40, 4
The 1 and the cutter 42 are movable back and forth toward the outer peripheral surface of the thin metal tube 3. Therefore, the rollers 40 and 41 are connected to the metal pipe 3
The outer peripheral surface of the can support the position opposite to the cutter 42. Further, the cutter 42 is capable of abutting its outer peripheral edge against the outer peripheral surface of the thin metal tube 3.

The end portion of the support ring 36 is rotatably driven by a belt 49 wound around a pulley 48 provided on the output shaft of the motor 47. The support ring 36 is the taper cup 35.
When rotated inside, the rollers 40 and 41 and the cutter 42 revolve around the thin metal tube 3. Further, the taper cup 35 is formed by the rod 50a of the first cylinder 50.
Based on the expansion and contraction of the, it is freely displaceable in the feed direction. Further, in front of the mounting portion 32 (on the right side of FIG. 1),
First clamper 33 for holding the upper thin metal tube 3
A second clamper 34 for holding the cut thin metal tube 23 behind the mounting portion 32 (on the left side in FIG. 1).
Are provided respectively.

These first and second clampers 33, 34
As shown in FIG. 5, the lower molds 52a and 52b and the upper mold 55 are
a, 55b. Of these, the upper mold 55a,
55b are rods 54a, 5 of the cylinders 53a, 53b.
By the expansion and contraction of 4b, it can retreat toward the lower molds 52a and 52b. Of the lower molds 52a and 52b, the lower mold 52a of the first clamper 33 is fixed to the upper surface of the table 25. In addition, the lower mold 52 of the second clamper 34
b is the second linear guide 56 provided on the table 25.
The thin metal tube 3 is movably supported on the upper side in the feeding direction. That is, one end of the table 25 (see FIG.
A second cylinder 57 is provided at the left end portion of the second cylinder 57, and the second clamper 34 is reciprocally movable on the second linear guide 56 in the feed direction by expanding and contracting the rod 57a of the second cylinder 57. I am trying.

Inside the thin-walled metal tube 3, the cutter 4 is attached.
A core 58 is provided at a position displaced from the abutting position 2 to the pipe making machine 1 side (right side in FIG. 1). As shown in FIG. 2, the cores 58 are provided at positions separated from each other in the axial direction of the thin metal tube 3 (the left-right direction in FIGS. 1 and 2), and each contact with the inner peripheral surface of the thin metal tube 3. A pair of guide elements 59, 59 that are in contact with or close to each other and a pair of slide bearings 6
0, 60, a pair of spacers 61, 61, and permanent magnets 62, 62 that are the first magnetic elements are combined in series in the axial direction. These constituent members 59, 60,
61 and 62 are through holes 63 formed in the central portions thereof.
A bolt 64 is inserted through a, 63b, 63c and 63d, and a nut 65 is screwed onto the projecting end portion of the bolt 64, and the nuts 65 are tightened so as to be fixedly connected.

The guide element 59 is made of a slippery material such as synthetic resin and is formed in a short cylindrical shape with the through hole 63a formed at the center in the axial direction. The guide element 59 on the side closer to the cutting position of the thin metal tube 3 cut by the cutter 42 is designed not to interfere with the cutter 42. That is, inside the thin metal tube 3, at least the cutter 42
A diametrically inner portion of the abutting position of is a hollow portion 66. Therefore, in this embodiment, as shown in FIGS. 1 and 2, the end edge of the guide element 59 is arranged at a position axially displaced from the cutter 42. However, this guide element 59
As described above, it is sufficient that at least the diametrically inner portion of the thin metal tube 3 at the abutting position is hollow. For example, as shown in FIG. 6, a concave groove 67 is formed over the entire circumference in the portion. Anything is fine.

The slide bearing 60 is constructed as shown in FIG. That is, the through hole 63b is formed in the central portion, and the rollers 68, 68 are pivotally supported at three locations in the circumferential direction. The rollers 68, 68 are preferably provided at evenly spaced positions in the circumferential direction as shown. The roller 68,
It goes without saying that the outer peripheral surface of 68 does not come into contact with the end surfaces of the axially adjacent members and is rotatable. Therefore, an appropriate spacer is provided at the portion where the slide bearing 60 is installed to secure a space between the rollers 68, 68 and the axial end faces adjacent to each other.

The permanent magnets 62, 62 are sandwiched between a pair of spacers 61, 61. In the illustrated embodiment,
Three ring-shaped magnets 62, 62 are superposed. The permanent magnets 62, 62 are preferably magnetized in the diametrical direction. This is to secure the positioning accuracy in the axial direction. However, a magnetized in the axial direction can also be used. A magnetic material 69, which is a second magnetic element, is provided on the outer peripheral surface of the thin metal tube 3 at a position facing the outer peripheral surfaces of the permanent magnets 62, 62.

At least one of the first and second magnetic elements may be a magnet, and the other may be a metal material having magnetism such as iron. Therefore, the first magnetic element can be a permanent magnet, and the second magnetic element can be a magnetic metal material such as iron or a permanent magnet. Alternatively, the first magnetic element can be a magnetic material such as iron, and the second magnetic element can be a permanent magnet or an electromagnet. The second magnetic element is supported and fixed on the upper surface of the table 25 so as to cover the outer periphery of the thin metal tube 3. During the cutting operation, a magnetic attraction force acts between these first and second magnetic elements to move the core 58 incorporating the first magnetic element together with the thin metal tube 3.

Since the cutting device of the present invention is constructed as described above, the core 58 to be inserted into the thin metal tube 3 can be attached or detached and the moving speed of the table 25 can be finely controlled as in the conventional device described above. There is no need to do it. That is, when the long thin metal pipe 3 is cut into a predetermined size by using the cutting device of the present invention, first, before starting the cutting work, the thin metal pipe 3 is inserted into the mounting portion 32 and the inside The child 58 is inserted into the thin metal tube 3. In this state, the pipe making machine 1 is operated to send out the thin-walled metal pipe 3 from the pipe making machine 1. If the tip of the thin-walled metal tube 3 passes through the mounting portion 32 by a predetermined size, the first and second clampers 33 and 34 hold the thin-walled metal tube 3 and the speed tuning servomotor 29 orbits to move the table. 25 is moved in the same direction at the same speed as the thin metal tube 3.

When the movement of the table 25 is started, the motor 47 is started to move the mounting portion 32 through the belt 49.
It revolves around the thin metal tube 3. Further, the first cylinder 50 extends the rod 50a and moves the tapered cup 35 backward in the feeding direction. With this movement, the support ring 3
6 moves relatively toward the inner surface of the taper cup 35,
The first to third arms 37, 38, 39 gradually project toward the thin metal tube 3. As a result, each arm 37, 38, 39
Rollers 40, 41 and cutter 42 pivotally supported at the tip of the
Is pressed against the outer peripheral surface of the thin metal pipe 3, and these members 40, 41, 42 revolve around the thin metal pipe 3 while revolving. Then, while the rollers 40 and 41 support the thin metal tube 3, the cutter 42 cuts the thin metal tube 3. The rotation speed of the support ring 36 and the moving speed of the table 25 are controlled in order to complete the cutting work before the table 25 reaches the end.

When the cutting of the thin-walled metal tube 3 is completed, the rod 57a of the second cylinder 57 is pulled in with the cut-out thin-walled metal tube 23 held down by the second clamper 34, and the metal tube is cut. Leave 23. When the cut thin metal pipe 23 reaches a predetermined position, the second clamper 34 is opened and the metal pipe 23 is discharged onto, for example, a conveyor (not shown). In this process, the table 25 is moved to the original position as fast as possible to prepare for the next cutting. When the table 25 is moved, the first clamper 34 is opened. The movement of the table 25 and the position detection of the metal tube 3 are detected by various sensors. Then, based on the signals from these sensors, a controller (not shown) sends a command to each motor and cylinder to operate them.

Since the cutting apparatus according to the present invention is constructed and operates as described above, it is not necessary to attach / detach the core or control the speed of a plurality of tables, and the metal tube 3 can be cut with simple control. . Moreover, the presence of the core 58 makes the cut surface clean. Therefore, the metal pipe cut by the cutting device according to the present invention is immediately advanced to the next step without requiring extra processing such as trimming. Further, since it can be operated by simple control as described above, the device does not become large or expensive.

Next, FIG. 8 corresponds to claim 4. 2 shows a second embodiment of the present invention. In this embodiment, the return movement of the core 58 is performed by a wire rod 70 such as a piano wire or a cable. That is, one end of the wire rod 70 is connected to the rear end of the guide element 59 that constitutes the core 58, and the wire rod 70 is connected.
The other end of is connected to the rod 71a of the cylinder 71. The cylinder 71 corresponds to a drawing means for drawing the wire rod. The position where the cylinder 71 is installed is the front end (the right end in FIG. 8) of the pipe forming machine 1 before the thin metal plate 2 is rolled. Alternatively, the cylinder 71 may be fixed to the table 25 or a member that moves together with the table 25. In the illustrated embodiment, the wire rod 70 is guided upward from the above position via the pulley 72a, is folded back at this upper position by another pulley 72b, and is connected to the rod 71a of the cylinder 71.

Further, a weight 74 which functions as a guide for position detection is fixed to the other end of the wire 70, and
A position detector 73 that can detect the position of the weight 74 is provided. The encoder 51 detects the feed speed and feed amount of the thin metal tube 3. Other configurations are the same as those of the first embodiment described above.

When the long thin metal pipe 3 is cut by using the cutting device configured as described above, the pipe making machine 1 is operated with the core 58 inserted into the thin metal pipe 3, and the thin metal pipe 3 is operated. Send out the metal tube 3. Then, when the thin metal pipe 3 has been sent out by a predetermined length, the first clamper 33 holds down the thin metal pipe 3. This first clamper 33
After the cutting is completed, when the core 58 returns to the pipe making machine 1 side, the core 58 is held at a predetermined position inside the metal pipe 3 to be cut next. Therefore, the installation position of the first clamper 33 is determined so as to suppress the outer peripheral surface of a part of the thin metal tube 3 corresponding to the predetermined position. During the cutting operation, the core 58 is pressed together with the thin metal tube 3 to move the table 25, and the mounting portion 32 including the core 58 is moved in the same direction at the same speed as the thin metal tube 3. Then, the thin metal pipe 3 is cut by the cutter 42 that revolves around the thin metal pipe 3 while revolving. After the cutting, at the same time as opening the first clamper 33, the cut thin-walled metal pipe 23 held by the second clamper 34 is pressed by the second cylinder 57 (see FIG. 1; omitted in FIG. 8). ), It is detached from the long thin metal tube 3.

During the above cutting work, the first clamper 3
The core 58 clamped at the guide element 59 portion on the side far from the cutter 42 by 3 moves together with the thin metal tube 3. After the cutting, the first clamper 33 is opened, and the core 58 is movable. Therefore, the cylinder 7
By contracting the rod 71a of No. 1 and retracting the other end of the wire 70, the core 58 is moved to the right in FIG.

The amount of drawing of the wire 70 can be detected by the detector 73 detecting the weight 74. Therefore, if the detector 73 detects the pulling of the wire 70 by a predetermined amount, the controller stops the pulling,
Make it stand by. Next, the other end of the wire 70 is fed out (loosed) so that the next cutting operation can be performed, and the core 58 is allowed to move at the same speed and in the same direction as the thin metal tube 3. State. Then, when the first clamper 33 is operated to perform the next cutting operation, the core 58 moves together with the thin metal tube 3 as described above, and the cutting operation by the cutter 42 is performed as described above.

By retracting the rod 71a of the cylinder 71 by a predetermined length, the core 58 is retracted by this retracted amount.
When the weight is moved back to the predetermined position, the weight 7
4. The position detector 73 can be omitted. Also, the cylinder 7
Instead of 1, the wire 7
It is also possible to adopt a winding device such as a reel for winding and pulling out 0. In FIG. 8, 75 is a die, 76 is a squeeze roll, 77 is a take-up belt,
78 is a torch. Each of these members 75, 76, and 77 constitutes the pipe making machine 1 and is not an essential part of the present invention, and therefore a description thereof will be omitted.

[0046]

Since the cutting device of the present invention is constructed and operates as described above, it is possible to continuously cut metal pipes with a simple structure and simple control. Therefore, the cutting device of the present invention is small and inexpensive. Moreover, the cut surface of the metal tube is beautiful, and after this cutting operation, it can be immediately sent to the next step, and a metal tube with high commercial value can be manufactured.

[Brief description of drawings]

FIG. 1 is a schematic side view showing a first embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of part A in FIG.

FIG. 3 is a view showing a mounting portion as viewed from the left side of FIG.

4 is a sectional view taken along line BB of FIG.

FIG. 5 is a schematic cross-sectional view showing a first clamper.

FIG. 6 is a side view showing another example of the core.

FIG. 7 is a front view showing a slide bearing.

FIG. 8 is a schematic side view showing a second embodiment of the present invention.

FIG. 9 is a schematic side view showing a conventional device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipe forming machine 2 Metal thin plate 3 Thin metal pipe 4 1st linear guide 5 1st table 6 1st motor 7 Rack and pinion 8 Cutting machine 9 Cylinder 10 Cutter 11 Support rotor 12 Gear part 13 Third motor 14 Second linear guide 15 Second table 16 Second motor 17 Rack and pinion 18 Core exchanger 19 Rotating shaft 20 Support arm 21 Stopper 22 Core 23 Cut thin metal tube 24 Clamper 25 Table 26 Cutting machine 27 units Platform 28 First linear guide 29 Speed tuning servo motor 30 Screw rod 31 Nut member 32 Mounting portion 33 First clamper 34 Second clamper 35 Tapered cup 36 Support ring 37 First arm 38 Second arm 39 Third arm 40 , 41 roller 42 cutter 43 through hole 44 compression spring 45 first pivot 46 Second pivot 47 Motor 48 Pulley 49 Belt 50 First cylinder 50a Rod 51 Encoder 52a, 52b Lower mold 53a, 53b Cylinder 54a, 54b Rod 55a, 55b Upper mold 56 Second linear guide 57 Second cylinder 57a Rod 58 Core 59 Guide element 60 Slide bearing 61 Spacer 62 Permanent magnet 63a, 63b, 63c, 63d Through hole 64 Bolt 65 Nut 67 Groove 68 Roller 69 Magnetic material 70 Wire rod 71 Cylinder 71a Rod 72 Pulley 73 Detector 74 Weight 75 Dice 76 Squeeze Roll 77 Pickup Belt 78 Torch

Claims (4)

[Claims] 1. A thin metal tube made of a non-magnetic material and thin and continuously sent from a pipe forming machine, and is reciprocally movable in the same direction as the metal pipe and in the opposite direction. In a thin-wall metal pipe cutting device provided with a table that moves at the same speed as the feed speed of the metal pipe when moving in the same direction, and a cutting machine that is provided on the upper surface of the table and cuts the metal pipe. A cutting device for thin-walled metal pipes, wherein the cutting machine satisfies the following requirements. A mounting portion that rotates around the metal tube is provided around the metal tube. The mounting portion is provided with a receiving member which is supported by a first pivot parallel to the metal pipe and revolves around the metal pipe while partially supporting the outer peripheral surface of the metal pipe. There is. A cutter is provided in a part of the mounting portion at a position substantially opposite to the receiving member in the diametrical direction with respect to the metal pipe so as to be capable of advancing and retracting with respect to the outer peripheral surface of the metal pipe. This cutter has a circular cutting edge as a sharp cutting edge,
The outer peripheral edge of the metal tube can be abutted against the outer peripheral surface of the metal tube while being supported by the second pivot parallel to the metal tube. Inside the metal pipe, a core is provided at a position displaced from the abutting position of the cutter to the pipe making machine side, and inside the metal pipe, at least a diametrically inner portion of the abutting position. Is a hollow part. The core includes a guide element that comes into contact with or comes close to the inner peripheral surface of the metal tube, and a first magnetic element provided at a position that is not aligned with the cutter. At a position on the upper surface of the table, which faces the outer peripheral surface of the first magnetic element via the metal tube, a second magnetic element formed in an annular shape and capable of inserting the metal tube is supported. At least one of the first magnetic element and the second magnetic element is a magnet, at least during the cutting operation between these first and second magnetic elements, a magnetic attraction force acts,
The core incorporating the first magnetic element moves together with the metal tube. 2. The cutting device for a thin metal tube according to claim 1, wherein at least one of the first magnetic element and the second magnetic element is a permanent magnet. 3. The apparatus for cutting a thin metal tube according to claim 1, wherein the second magnetic element is an electromagnet and the first magnetic element is a magnetic material. 4. A thin metal tube which is continuously fed from a pipe forming machine, is provided below the metal pipe, and is reciprocally movable in the same direction as the metal pipe and in the opposite direction. A cutting device for a thin-walled metal pipe provided with a table that moves at the same speed as the feeding speed of the metal pipe when moving, and a cutting machine that is provided on the upper surface of the table and cuts the metal pipe. Is a cutting device for thin-walled metal pipes, which satisfies the following requirements. A mounting portion that rotates around the metal tube is provided around the metal tube. The mounting portion is provided with a receiving member which is supported by a first pivot parallel to the metal pipe and revolves around the metal pipe while partially supporting the outer peripheral surface of the metal pipe. There is. A cutter is provided in a part of the mounting portion at a position substantially opposite to the receiving member in the diametrical direction with respect to the metal pipe so as to be capable of advancing and retracting with respect to the outer peripheral surface of the metal pipe. This cutter has a circular cutting edge as a sharp cutting edge,
The outer peripheral edge of the metal tube can be abutted against the outer peripheral surface of the metal tube while being supported by the second pivot parallel to the metal tube. Inside the metal pipe, a core is provided at a position displaced from the abutting position of the cutter to the pipe making machine side, and inside the metal pipe, at least a diametrically inner portion of the abutting position. Is a hollow part. The core includes a guide element that is in contact with or close to the inner peripheral surface of the metal tube. During the cutting operation, the core is moved together with the metal tube as the clamper that moves together with the table holds down the outer peripheral surface of the core via the metal tube. One end of the wire is connected to the rear end of the core,
The other end side of the wire is allowed to move the core during the cutting work, and is connected to a drawing means for drawing the wire after the cutting work is completed.